OCON is a musical instrument (a MIDI-controller to be precise) with wich hobby and semi professional musicians can create the base for complex music easily. To enhance the possible ways to work with this instrument the musician can connect it to a great variety of other electronic instruments.
OCON is based on the circle of fifths. To put it simple, there are various chords arranged in a circle. You can recognize which chords sound harmonious respectively distant.
Music generally works with acoustic patterns. These patterns can be hard to imagine before or while making music since you often -and at least while improvising- don't have a visual counterpart. OCON creates this connection between the visual and the acoustic by inverting this idea. The musician draws a visual pattern onto the virtual circle of fifths which in turn creates an acoustic pattern.